First of all, congratulations on bringing Lily home.

My advice is not to worry about the growling and hissing. They will work things out and it will be okay. When I first brought Tanner home, Emily ignored him for the first couple of days and then hissed and growled at him for a few more. But once she realized that he wasn't going anywhere they made their peace with each other. Give it time and patience (and a couple of glasses of wine wouldn't hurt either )

Now can we have some pictures....